Cocoa may help diabetes as well as heart failure

Dr. Francisco J. Villarreal of University of California, San Diego, said epicatechin is a flavonoid found in dark chocolate.

After three months, the researchers looked at changes in mitochondria volume and the abundance of cristae, are internal compartments of mitochondria necessary for efficient function of the mitochondria.

"The cristae had been severely damaged and decreased in quantity in these patients," Villarreal said in a statement. "After three months, we saw recovery — cristae numbers back toward normal levels, and increases in several molecular indicators involved in new mitochondria production."